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Editors' Choice

No touching, please

Sacha Vignieri

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European badgers have been blamed for the transmission of bovine tuberculosis in the United Kingdom and, despite much evidence to the contrary, have endured regular and repeated culling efforts based on the assumption that their lethal removal decreases the spread of the disease. Woodroffe et al. used GPS and contact collars to record the degree to which badgers and cattle actually come into contact. Despite finding that badgers prefer to spend their time in pastures, they recorded no direct contact between the two species, with badgers tending to say at least 50 m from cattle. Thus, any transmission between these two species seems to be environmentally mediated, a result that could be instrumental in targeting nonlethal ways to prevent the spread of the disease.

Ecol. Lett. 10.1111/ele.12654 (2016).

Host Responses

An appetite for tolerance

Kristen L. Mueller

The proverb “feed a cold, starve a fever” may contain a kernel of truth after all. Animals from insects to humans display certain types of behaviors when they are sick, including reduced appetite and social withdrawal. To better understand the importance of these behaviors, Wang et al. studied the effects of sickness-induced anorexia in bacterially or virally infected mice. They found that whereas nutritionally supplementing mice improved their overall survival of influenza infection or viral sepsis, it killed mice infected with Listeria monocytogenes or subjected to bacterial sepsis. These effects were independent of pathogen load and resulted rather from nutrition-based differences in the ability of the mice to tolerate the pathogen, owing to the different metabolic pressures facing the host.

Cell166, 1512 (2016).

Cellular Biochemistry

Activating chromatin by stretching

Guy Riddihough

Cells are subject to many mechanical stresses. These forces can profoundly alter cellular biochemistry. Tajik et al. used a magnetic bead on the surface of a cell to apply a shear stress to the cell's nucleus. A linear array of fluorophoremarked genes moved apart, indicating that their chromatin was being stretched. Stretching activates transcription of the marker genes within seconds, suggesting that the stretching effect, propagated through cytoskeletal tension, is direct, with the degree of stretching correlating with the degree of gene activation.

Nat. Mat. 10.1038/NMAT4729 (2016).

Quantum Optics

Toward quantum nanophotonics

Ian S. Osborne

The quantum properties of light are well studied and have been extensively used to reveal some of the fundamental aspects of quantum mechanics. Efforts now are under way to leverage the “quantum advantage” offered by quantum entanglement for practical applications such as enhanced imaging, sensing, and communications. A viable quantum technology, however, will require a shift from the optical bench to a miniaturized on-chip platform. Holtfrerich et al. show that the quantum properties of optically entangled images are preserved as they are transmitted to distant plasmonic structures, where they convert to nanometer-scale electronic excitations before being converted back to light.

Optica3, 985 (2016).

Future Faunas

Global change and tropical birds

Andrew M. Sugden

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In much of the world, terrestrial organisms face the twin challenges of climate change and land use by humans. In a survey of a variety of tropical ecosystems in Costa Rica, Frishkoff et al. assessed the long-term responses of >300 native bird species to these challenges. Bird species from drier habitats showed greater ability to cope with the conversion of natural habitat to agriculture and with the drying trend in the region. Hence, these dry-habitat species are predicted to be relatively robust to future global change, whereas moist-habitat species may decline. The result will be a more homogenized and depleted fauna.

Ecol. Lett.19, 1081 (2016).

Materials Science

Stabilized dyes as dense glasses

Phil Szuromi

The photostability of organic dyes can vary greatly between different crystalline polymorphs (packing arrangements), but similar effects have not been observed in amorphous or glassy materials. Qiu et al. studied the photostability of a common azobenzone dye (Disperse Orange 37), which can undergo photoisomerization, at different glass densities. Photostability was increased by a factor of 50 in glasses formed through physical vapor deposition on a substrate, relative to less dense glasses that formed simply by cooling the liquid. The highest photostability was observed for the densest vapor-deposited glass, which formed at substrate temperature of 260 K.

J. Am. Chem. Soc. 10.1021/jacs.6b06372 (2016).

Robotics

Can you feel what I feel?

Marc S. Lavine

By combining tactile sensations of hardness, ductility, shape, and surface texture, and then comparing these with our previous experiences, it is possible to safely grasp a random object placed in our hands without needing to see it. However, most robotic systems still lack this combination of abilities. Rather than focusing on better hardware, Sommer and Billard developed a control strategy for prioritizing the movement of individual digits and feedback from sensors, while limiting the applied force and remaining within the limits of joint movement. This makes it possible to construct a multitouch hand that can adaptively grasp an object at several points at once and probe with some digits while gently holding an object with the others.